Gary Sobol of Boulder started and leads exercise classes at the YMCA in Boulder to help others like him with Parkinson's disease. (Helen H. Richardson, The Denver Post)

BOULDER — Even after two years of medical and physical therapy to treat Parkinson's disease, Joan Knapp had trouble walking unassisted and getting up from a chair.So when she attended her first Parkinson's Boot Camp exercise class at the Boulder YMCA last March, her jaw dropped. She watched, incredulous, Parkinson's patients carefully rising from their chairs, and then picking them up to stack against the wall."When I was first diagnosed, I couldn't walk or talk or swallow," said Knapp, a trim woman diagnosed with Parkinson's disease about two years ago."I come to Gary's class three times a week, and I've improved considerably. When I came here, I was teetering all over the place. I function like a normal person now. I can do so much more than I ever thought I could."That's exactly what Gary Sobol, 73, wants for everyone in his Parkinson's Boot Camp class, which draws 20 to 50 participants and meets three times a week at the Mapleton branch of the YMCA of Boulder Valley. Sobol, a former marathon runner, also has Parkinson's.After his diagnosis, he researched the condition and found that physical therapist and physicians were recommending stretching and exercise."There's been a lot more focus on exercise and Parkinson's recently," said Dr. Avrom Kurtz, a neurologist at Exempla Good Samaritan Medical Center."Doctors have always told patients that exercise is beneficial, but now studies show how helpful it is for treating or mitigating symptoms. A New England Journal of Medicine article showed that tai chi can help with a patient's posture and balance. I have several patients who go to Gary's class, and a lot of times, you can see dramatic improvement in regaining function of things lost as a result of Parkinson's."Sobol teaches his class on Mondays, Wednesdays and Fridays. Some people joined the YMCA specifically to take that class.Group exercise classes that target specific populations are becoming increasingly popular. Other health clubs and fitness centers, including the Duncan Family YMCA in Arvada, offer classes for people with Parkinson's, balance problems, diabetes and multiple sclerosis. Sobol is one of the rare instructors who knows firsthand what participants experience."When you see Gary, and know he has Parkinson's, and watch him lead, it's a very encouraging situation," said Paul Browne. He was diagnosed with Parkinson's about eight years ago and faithfully attends Sobol's class."Look at that guy! Look at what he's doing! It would be a lot of fun watching a 20-year-old teach the class, but when it's someone in their 70s, it sets the bar for you. Most guys his age aren't doing as much as he is."When he teaches, Sobol wears shorts that show off his still-muscular legs, a green Parkinson's Boot Camp T-shirt that the Davis Phinney Foundation printed for his class, and a yellow Livestrong wrist band.He designed Parkinson's Boot Camp, which began last January, a little over a year after being diagnosed with the condition."As a recently diagnosed Parkinson's patient, I was in bad shape," he said."I couldn't get out of bed by myself. My handwriting was impossible. I couldn't get out of acar by myself. My left foot was dragging. So I did some research and learned exercise seemed to be the trend in Parkinson's research. I took exercise classes and started to get my quality of life back. I was able to hike and run again. I was writing checks again."Members of the Boulder YMCA took note of Sobol's improvements. When he explained what he was doing to counter the Parkinson's symptoms, they suggested leading an exercise class targeting others with the same condition.Sobol got in touch with neuroscientist and physical therapist Dr. Becky Farley, who created a series of exercises specifically for people with Parkinson's. He trained through her NeuroFitness Center of Excellence for Parkinson Exercise and started his class at the YMCA last January.The class lasts 90 minutes. It incorporates the physiotherapy exercises that Farley created for people with Parkinson's. The movements are exaggerated and broad to counter the stiffness imposed by Parkinson's. Sobol has the class count aloud, shouting, as he leads exercises, which helps counter the diminishing effect that Parkinson's has on vocal cords."These things do make a big difference," Kurtz said."What the disease process does is cause people to move more slowly. Their arms become stiff. Their steps diminish. They shuffle instead of picking up their feet. Their voice gets quieter and quieter. To challenge the disease, you have to counteract all those things — move around a lot, do quick movements, make your feet move bigger, swing your arms wider, do the opposite of what the disease is trying to make your body do."Sobol, who has triumphed over two bouts with cancer as well as coping with Parkinson's, credits his own exercise class with helping him get back to hiking."I hadn't climbed in years," he said."I did Mount Chapin in Rocky Mountain National Park, and Twin Sisters, which is amazing because that last half-mile is a big rock pile, and very difficult for someone with Parkinson's. You've got to plan every move you make — put your pole here, and your foot here. When I got to the top of that mountain, and down again safely, I realized I can keep doing this!"Currently, between 1 and 2 percent of North Americans are affected by Parkinson's Disease. Kurtz predicts that number will double by 2030."It's going to be a huge medical crisis for those patients, and additional resources like this will help them," he said.Claire Martin: 303-954-1477, cmartin@denverpost.com or twitter.com/byclairemartinAssistant instructor Richard Pagel helps Parkinson's sufferer John Mandis with balance during the class.